99civ

Just went through every search result and have a few more questions... Week or so ago, I found my radiator had cracked at the top so I replaced it with a oem replacement and refilled it with coolant, bled the system, etc. Car runs fine and everything is dandy but I checked on my fluid levels again and my reservoir was practically dry again. Radiator looked fine as far as looking inside from the cap hole. My biggest concern is a blown HG obviously. As far as I can see from looking everywhere, I see no leaking coolant. I checked my oil, it looks like oil, no white residue but it seemed a little more "liquid" than normal. I also could be paranoid and will compare to my b18 later to see if the two oils are different shades. I read in all the threads that a leak down test really doesn't do anything to tell you if it's blown or not. Any help, love you guys and all the knowledge.
_Bad_
-Disappearing coolant
-might be in my oil

_Good_
-Car runs fine
-CEL is code 1(o2 sensor)
-no smoke in exhaust or anywhere else
-no noticeable leaks
-car has never over heat

Former User

Despite the bleed, there was probably still some air trapped in the cooling system. Just top off the radiator and reservoir with coolant and go from there.

Solomon1468

Have you refilled with coolant since you noticed the overflow tank was empty? If you do that, and it goes dry again, with absolutely no visible leaks, probably the head gasket. Are you getting good pressure in the upper and lower hoses when the engine is warm?

99civ

I'll check the hoses and the reservoir after tonight. I have to go pick up one of my labs about 20sh minutes away so it will be about an hour round trip.

motegicivic

Do a block test

apexi_rsx

could be a bad and slow leaking radiator maybe get some dye and a black light and test it with the motor running and idling.

99civ

Went outside after driving to my moms to get my dog and back. Roughly about an hour round trip. When I pulled into my driveway I popped the hood and lower/upper both have solid pressure during idle. No oil in my reservoir but oil on the dipstick still looks "wetter" than normal. I may change the oil on my day off this week and see if it re-occurs. Are there any other signs of head gasket? I could do a block test on my day off, autozone rents them right?

99civ

You think with it being brand new? I mean I'm sure its possible. I sell for a living so, "there's a lemon in everything..." comes out of my mouth a lot..

sodapopsmash

you might try a new radiator cap, the coolant may be seeping out while driving and then dissipating on the hot radiator so it doesn't look wet anywhere when you check. I recently had a problem with my coolant blowing into my overflow and filling it up every few days. Replaced radiator, cap, low temp thermostat, water pump. Turned out to be a mildly blown head gasket, in a spot where no oil/coolant ever mixed, so it was hard to diagnose. If your overflow isnt filling up and car never overheats it's probably not HG though.

frankenghia

If it was a slow leak you wouldn't be going through coolant as fast as you say you are. If it was external you would see it. Just because your oil isn't milky or coolant not oily doesn't mean its not a hg. Both my hondas needed hgs and neither one had any smoke, oily coolant, milky oil but both were eating the coolant. My overflow never ran over nor did my car run hot unless the coolant level got too low.... Another way to tell is pull your spark plugs and see if one of your pistons looks cleaner than the others. If its a bad enough leak you will see one or more being cleaner. Just a free idea for you to check...

Max Kling

There are many different ways to check. You can do a carbon test of your coolant, but honestly I would go ahead and do a compression test. If you get lower than normal numbers on sister cylinders then you shall know.

You need to check for leaks around any heat source. Like exhaust, the radiator, or anything that is hot enough to evaporate the coolant before it lands on the ground.

Also how did you fill your system after you replaced the radiator?

Also exactly how much are you "loosing"?

There is a lot of good suggestions and about 1000 different ways to test, so until you start investigating its all just speculation.

99civ

I appreciate all the feedback..
-"Filled" my system by filling up the radiator then bleeding it to 'two' fan cycles then filling the reservoir up.
-Yesterday when I posted this, I had an empty reservoir. Filled it to max and I'm about a few points over half now.
-I've never messed with cooling aside from adding coolant so I'm learning as I go. I replaced the radiator, etc... by the book(easy at the hardest!).. My biggest fear again is a HG because this IS my DD.

99civ

Also the car only has 115,000 on it and was owned by an old lady prior to me with all honda receipts for maintenance.